Air-circulating system for industrial ovens



lV/TNESSES:

W. C. EHMKA.

AIR CIRCULATING SYSTEM FOR INDUSTRIAL OVENS. APPLICATION FILED J AN. 3. 1921.

Patented July 4, 1922.

4 SHEETS-SHEET 1.

INVENTOR.

Di- C. Ma.

% A TTORN/JV.

w. c. EHMKA} AIR CIRCULATING SYSTEM FOR INDUSTRIAL OVENS.

APPLICATION FILED JAN. 3. I921.

' Patented July 4, 1922.

4 SHEETSSHEET 2. {a 27 $1 22 I Ill E I I V l 7 IV/11818755 Wwm m/ y M W. C. EHMKA.

AIR CIRCULATING SYSTEM FORJNDUSTRIAL OVENS.

APPLICATION FILED JAN-3,1921! Patented July 4, 1922.

4 SHEETS-SHEET 3-' I I 1 3 INVENTOR.

hf C. M @romwsyp WITNESSES. 3

0mm S w. c. EHMKA. AIR CIRCULATING SYSTEM FOR INDUSTRIAL OVENS.

I APPLICATION FILED lAN.'3,1921- 1,421,429. Patented July 4, 1922.

4 SHEETS-SHEET 4.

WITNESSES: INVENTOR.

k/QCM A TTORNE Y.

WILLIAM C. EHMKA, DETROIT, MICHIGAN, ASSIGNOR TO DETROIT SHEET METAL WORKS, OF DETROIT, MICHIGAN, A PARTNERSHIP FIRM.

AIR-CIRCULATING SYSTEM FOR INDUSTRIAL OVENS.

To all whom it may concern:

Be it known that 1, WILLIAM C. EHMKA, a citizen of the United States, residing at the city of Detroit, county of Wayne, State of Michigan (whose post-ofiice address is 453 KitchenerAveJ, have invented certain new and useful Improvements in Air-Circulating Systems for Industrial Ovens, and

. declare the following to be a full, clear, and

exact description of the same, such as will enable others skilled in the art to which 'it pertains to make and use the same, reference being had to the accompanying drawings, which form a part of these specifications.

This application is made as a division required by the Patent Office, of a prior application, Serial No. 388,97 4, filed under date of June 14, 1920, and the former filing date is hereby reserved.

The objects of my invention are to provide an efficient air circulating system for an-industrial oven, to separate the light air from the heavy gases as they form .during the baking-or drying process in the oven.

Another object is to provide a double fan system whereby the circulating and exhaust fans may operate as one unit, and produce a I I inafter described.

Fig. 3 is a side view of the oven showing the air chambers and its connection to the system.

Fig. 4 is a rear view of circulating system.

Fig. 5 s a sectional view AA as is the oven and the Specification bf Letters Patent.

shown on Fig. 1, showing the-interior circulating and heating units.

Fig. 6 is a sectional view --BB-, as is shown on Fig. 1,'showing the bafile plates and heat units.

Fig. 7 is a sectional view CC as is shown in Fig. 2, showing the arrangement gf the plenum chambers and exhaust chamers.

I will now describe more fully the detailed construction and the working parts thereof, referring to the accompanying drawings and the marks thereon.

The construction of the oven may be of any desired form, or arrangement of parts and materials to form suitable heat retaining walls. The followin description is a preferred 'form, and is t e one in present use in connection with the air circulating system herein described and claimed.

The oven walls consist of portable rectangular panels which are fastened together in erecting the oven, The floor is constructv ed of a suitable heat retaining material, and placed on the oven foundation. Mounted on the floor slabs are the wall panels 2, comprised of a sheet metal jacket'riveted together to form a hollow rectangular panel,

' and filled with a heat retaining material.

These slabs are securely fastened together at the edges by means of lap joints and screws. The joint also provides a space between the edges of the panels which is filled with a loose heat retaining material. thus 'ving the panel room to expand. The pane s are held in place by means of angle irons 3 and 4, securely fastened to the edge of the floor slab and allowing the wall panels to slide freely therein. The wall corners 7 and 8 are separatennits but of similar construction and joined to the wall-panels in the same manner. At the top of the wall slabs are securely fastened angle irons 5, as is shown in Fig. 5 and Fig. 6, and supports the roof T-bars 6. Between the T-bars are placed the roof slabs 9, which are of similar construction to the wall panels. .The opening between the roof panels is filled with a loose heat retaining material, and the panels are held in place by the cover plates 16 by means of screws and slotted holes, to allow for the expansion due to the oven heat. The roof panels extend slightly beyondthe inner edge of the' wall panels to form a seal for retaining the loose heat retaining material in Patented July 4, 192 2.

I Original application filed June 14, 1920, Serial No. 388,974. Divided and this application filed January Serial No. 434,277.

construction thereof.

The walls may be made of any desired thickness for retaining heat to any desired degree. And likewise the panels may be made of any desired width.

The oven and circulating system may be of a single unit, or in a series of ovens placed side by side and the circulating system extending through all of the units or ovens.

Inside the oven, and supported on the walls are the heat units 42, so placed as tov come in contact with all of the airfrom the circulating fan as it enters the oven through the portals 34, and by means ofvthe baflie plates 35. Theheat units may be of any desired type. I

In connection with the ovenas described, or any type of oven, is the air circulatin system comprised of the double fans 22 and 23. These fans may be located at the top of the oven or at any convenient position suitable for making connections. The double fans are placed on a common shaft and sup- .ported by the main pedestal 25, and

operated by the drive belt 24. Fan 23 is the circulating fan drawing its supply of air for the oven from the exhaust chamber 26 and the breather'27. The exhaust chamber 26 is located in the roof of the oven, and receives the light heated air from the oven therein, which is then mixed with the fresh airfrom the breather 27 as it is drawn back in the circulating fan in such proportions as may be desired by means of the damper 28. The supply coming through the exhaust chamber 26 may also be regulated by means of damper 29 placed in the circulating pipe 30. The supply fan 23 exhausts the a1r into the circulating pipes 31 and 32, and into the lower plenum chamber 33, and thence distributed through the portals 34 intothe oven.

Inside the oven and opposite the portals 34, are thebaffie plates 35 which start the fresh air in an u ward direction, passing through the heat COIlS, or units, and thence diffusing through the entire oven.l The heavy gases and fumes from the baking materials settle to the bottom of the oven and are drawn off through'the ortals 36 into the exhaust chambers 37. hambers 37 are exhausted by means of the exhaust fan 22, drawing the air through the pipes 38 and 39, and exhausting same through the outlet 40 into an open chimney, The. amount of air drawn from the exhaust chambers 37- may be regulated by means of the dampers .41 placed in the exhaust pipes 38 and 39.

' by Letters In describing the above invention, I desire it to be understood that the same is merely illustrative of the air circulating system now in use, and I do not wish to be confined to the precise construction and arrangement ofparts is shown. The above description is to include any substitute construction and arrangement of parts which are obviously equivalent to thoseherein described. I

Having fully described my circulating s stem and workin parts thereof, what I 0 am as m atent is: p

1. Inan oven, in combination with an air heating apparatus, a circulating system comprising a double fan unit, means for operating said fan, said double fan unit consisting, of an exhaust fan and a circulating fan, exhaust chambers means for connecting the exhaust fan to the lower exhaust chambers of the oven, circulating chambers and means. for connecting the circulating fan withthe upper and lower chambers of the oven. '2. In an oven 1n comblnatlon wlth an an heating apparatus, a circulating system comprising a circulating fan, an exhaust fan, means for operating same, upper and lower circulating air chambers, means for connecting the circulating fan thereto, means for distributing the air through the oven, means 'for connecting the exhaust fan to the exhaust chamber and means for regulating the flow of'air. Y i

3. An oven in combination with an air heating apparatus, a circulating system com-v prising a circulating fan, an exhaust fan, means for operating same, means for connecting the circulating fan with the upper and lower parts of the oven, means for connecting the exhaust fan with the lower part of the oven, and means for regulating the flow of air through each, and means for distributing the air through the oven.

4. An oven in combination with an air heating apparatus, a circulating .system, a circulating fan, an exhaust fan, means for. operating same, upper and lower exhaust invention and desire to secure chambers, an intake pipe connecting the circulating fan with the upper exhaust chamber of the oven, a separateair intake breather also connected with the circulating fan intake,- means for regulating the proportions of hot air from the vexhaust chamber to the fresh air from the intake breather as it enters the fan, and means for distributing same through the oven, and means for exhausting the air from the oven through the exhaust fan.

In testimony whereof I, WILLIAM G.

,EHMKA, sign these specifications.

WM. C. urn rm.

Witnessesr Josnrrr I-l. MARTIN, Henry D. Fansnn. 

